According to the invention, the method for operating a laser scanner has the following steps: scanning at least three spatial points of an object; ascertaining coordinates of the respective spatial point, wherein the laser scanner forms the coordinate origin and the coordinates comprise a distance and at least one angle; defining a vicinity around a central spatial point having at least two spatial points; aggregating coordinates of the spatial points in the defined vicinity; and replacing coordinates of the central spatial point by the aggregation of coordinates of the spatial points in the defined vicinity.
Ascertained coordinates of the central spatial point are advantageously replaced by the aggregation of ascertained coordinates of the spatial points in the defined vicinity by a mean value of ascertained coordinates of the spatial points in the defined vicinity. Therefore, ascertained coordinates may be replaced in a targeted manner by an aggregation of coordinates, preferably by a mean value, taking consideration of secondary conditions, which reduces the measuring error and therefore increases the surface precision during scanning.
It has been shown that during the operation of a laser scanner, an aggregation of coordinates of spatial points in a defined vicinity increases the surface precision of the object to be scanned. According to the invention, the spatial points ascertained by the laser scanner are processed, either in real time or with a time delay. For this purpose, a vicinity of scanned spatial points is formed. One of the scanned spatial points of the vicinity is defined as the central spatial point and at least two scanned spatial points are defined as adjacent to this central spatial point in the angle space. Coordinates of ascertained spatial points in the vicinity are aggregated, which results in a minimization of the measuring error.
Aggregation in the meaning of the invention refers to filtering of the coordinates of ascertained spatial points in the vicinity of a central spatial point; during the filtering, items of coordinate information of the spatial points, preferably the items of coordinate information of all spatial points in the vicinity are considered; and the coordinate of the central spatial point is replaced by an aggregated coordinate. This aggregation is repeated for further registered spatial points, preferably for all registered spatial points. For this purpose, a further vicinity is defined in relation to a further central spatial point, and further scanned spatial points are defined as adjacent to this further central spatial point in the angle space. During the aggregation, there is therefore no data reduction, the number of the spatial points is not reduced, nor is the number of the coordinates reduced. Three secondary conditions are presumed here:
i) the scanning step size from one spatial point to the next spatial point is substantially constant,
ii) the surface of the object to be scanned is substantially continuous, and
iii) the scanning step size is in the order of magnitude of the continuity of the surface of the object to be scanned. Such an aggregation of coordinates is performed with little technical effort and very rapidly.
The spatial points are advantageously scanned by the laser scanner using a scanning step size of an angle, and while using the scanned spatial points, a vicinity is defined, wherein at least those scanned spatial points, which are less than or equal to two scanning step sizes of the angle around the central spatial point, are considered to be adjacent to the central spatial point.
The aggregation of coordinates of the ascertained distance vectors in the defined vicinity is advantageously weighted by a settable filter. The aggregation of the coordinates in the vicinity is therefore formed in a manner weighted by a settable filter, whereby the information content of the ascertained distance vector remains uncorrupted in an objectively comprehensible manner. The standard deviation of the noise is thus decreased by the filter.